I'm trying to merge two BVH files using a text editor; although I cannot get the two BVH files to merge seamlessly without jumping ? I'm hoping someone has experience in this area, specifically using a text editor.

Done something kind of similar sounding in the past but I didn't go with flip. I don't have houdini open right now, but off the top of my head, you could try ripple solver on a grid and then extrude volume the cache. If extruding your rippled grid is messy you could ray a highish poly grid onto the cache for tidier collision surface geo, then volume extrude the rayed grid and cache (You may not need to extrude if your polys allow for surface collision instead of volume on your static object dop node). Plug it into your sim as a static deforming object. You could then popsolve points down from above which land onto the ripple/undulating surface, which instance packed rigid body objects. If you definitely need flip though, this approach may not be so useful.

Thanks for your reply! Unfortunately, the FLIP is, I'm guessing, partially incidental--what I'm looking for is a rigid torus dropped on top of a deforming mesh--I don't want any fluid animation. I included the FLIP elements as I'm assuming that somewhere in there is the source of why it's not working.
Also, in the "real" project, the fluid-like solid mesh is done, big and dense and pretty, after a four-day sim. I am out of FLIP-land and into crass ol' geometry-land now.
I did mess with the density of the RBD torus, but that didn't really do anything as the collider itself is a non-density object.
The quest continues. (Your example was great guidance on combining FLIP and RBD, though!)

Here are a few things to know:
First, you should never use hdefereval.executeInMainThreadWithResult from the main thread, obviously, it'll always lock the session.
Now, what's going on with user's Thread instances is a little bit odd from a viewpoint of a regular Python interpreter. When you join(), you tell other threads (main thread, in our case) to lock and wait. This seems to work fine with Houdini, until you start making calls to Houdini API from your thread, (hou.expandString() in your case)
For this reason, there's a hdefereval.executeDeferred(callback) method exists, which doesn't block, but if you need to get something back from your callback, you'd have to take care of this yourself, there are many ways to do this, for example using Queues. This is common producer-consumer pattern.
Hope this helps.

Hi, this effect sounds neat. I don't know if you'll have much luck with the rigid body solver in this case the way you've got it (I could be very wrong though so anybody please chime in!). Shuffling your DOP setup around and changing the density of the RBD object seems to do sort of what I think you were saying? The torus is affected by the FLIP sim, but in a rigid sort of way. Otherwise, I'd be looking for ways to transfer the motion of the flip sim to the torus in SOPs post-sim.
EDIT: Also if you're getting any jittery stuff on your object you wanna smooth out, try just using a little bit of a lag or filter CHOP on P and blend it back in. It can help with some small stuff.
meshtest_jamesr.hipnc

I have a meshed FLIP sim (cached out, .bgeo files read back in) that I want to use as a "solid" object and have a rigid body rest on top of it (the idea is that something solid "ripples" psychedelically and the objects resting on top of it move as the ripples go underneath--but the original object is still a solid, and the objects don't sink into it). I just can't get it to hold up, however--when the RBD object is initially "dropped" onto the fluid mesh, it bounces and settles as expected, and does okay with simple early movement, but eventually the collisions become less and less precise and the RBD object just sort of sinks in. How can I get the mesh to read as just a run-of-the-mill deforming object?
I've tried RBD solver, bullet solver (obviously doesn't work with the shape of the mesh), volume and surface collisions, jacking up collider volume resolution to make sure all the little waves are getting captured, and boosting the substeps, but the result has been pretty consistent (except more substeps = super jittery RBD as it's reading all of the little pre-big-movement mesh ripples). On the attached setup (a simpler version of the project giving me trouble) I even ran the meshed surface through a "clean" just in case any of the lingering velocity attributes were throwing it off, but that didn't help either. I'm wondering if the fact that the topology itself changes so much might be the problem, but if so I'm not sure how to fix that.
Thanks for any suggestions!
flipmeshtest.mp4
meshtest.hiplc

To be able to use bake by mesh name in Substance Painter, I need to prepare the model in Houdini by giving names to subparts for both high and low resolution mesh, as he explains in the first 2 minutes in video below. How do I create named subparts in Houdini, it doesn't work with groups, (he shows it for Maya, e.g. top_high, top_low)

I've just done a in-place upgrade from windows 7 to windows 10. And now houdini is giving me this strange login request box. Has anyone ever seen this before or perhaps someone can suggest a solution. I have no windows login password so I don't know what to type here....
Many thanks

Read the color from the polyline/polygon using p.attribValue(‘Cd’), convert it to hex format and use it instead of black in write_path().
http://www.sidefx.com/docs/houdini/hom/hou/Polygon.html#attribValue
https://qiita.com/kit2cuz/items/0acc5b6352129db587cb
and learn this
and I wonder at the end why you need Illustrator
Have a nice day

Hi there, I am trying to define the shape of lightning using vex in a wrangle sop
A lightning path has forks that split from any given path, creating other paths with almost identical properties to the main path. To that end I created a path struct but I can't figure out how to get it to store its 'forks'. The same issue would arise if I instead stored the parents instead of the children.
I am defining a path of lightning as so:
struct lPath
{
lPoint source;
lPoint sink;
float energy;
lPath forks[];
void setSource(lPoint newSource)
{
source=newSource;
}
void setSink(lPoint newSink)
{
sink=newSink;
}
void setEnergy(float newEnergy)
{
energy=newEnergy;
}
void create()
{
addprim(0,"polyline",source.num,sink.num);
}
}
my issue is that I can't include a reference to itself due to infinite recursion, which is why in c++ I would use a reference
lPath * forks[];
Is there any way to solve this using vex?
Kind Regards
George

Hi, im learning Houdini, while follow training course, usually in VOP there are keyword used for Bind node like Up, Radius
I try to learn more about those keyword for possibility in use VOP more effective.
There is DOC about Keyword reserved for VEX like this: https://www.sidefx.com/docs/houdini/vex/lang.html#reserved
Is there anything like that for VOP ? thank you

I have a point attribute set on some particles when they emit, I can't get vellum grains to constraint only the point attribute ?
Vellum in DOPs; vellumObject > vellumSolver > Output but I don't see the grains on the particles in the viewport either ? Vellum Constraints in SOP's is fetching the attribute in Define Pieces from Attribute but that attribute is not constrained ?

i have this geo and i want to apply random textures from a folder hierarchy.
i friend of mine helped with some python code, so now i can select a folder randomly and then get the first image of the sequence with a little tweaking i managed to plug it in a quickshade and converting the file numbers to $F4 or $F3. so it should read the sequence
BUT!! although i have the iterations attribute of the foreach meta node as a seed for the python script, the same image applies to all primitives.
What is missing?
Side question: why are the uvs rotating?
any tip much appreciated, houdini forums are bit dry right now
random_sequences.hip
untitled.bgeo

Hi,
I am deleting something but new connections form:
I would like to delete like you would with the Direct Selection tool in Illustrator, instead of the using the - tool in Illustrator while in Pen mode.
Hope someone knows the answer.
Thanks.